A big belly is just as dangerous for the heart as being heavy, a new study has
found.

Having a waistline that falls into the overweight or obese category can increase the risk of dying of heart disease four-fold, according to the research.

Fat carried around the middle of the body - giving people an apple shape instead of a pear - is different to fat on the hips and bottom and is more dangerous to health.

A person's waist circumference is therefore defined as the measurement around their middle, rather than their trouser size, as most people wear their trousers around their hips.

According to the researchers, a waist circumference of more than 40 inches for men and 34.6 inches for women classed as overweight. A healthy waist circumference for men is defined as less than 37 inches and for women less than 31.4 inches.

The study examined the increased heart disease risks for people based on their waistline girth and their body mass index (BMI). BMI is calculated by dividing a person's weight, measured in kilos, by their height, in metres. It has been criticised as some athletes with lots of muscle but little fat would be classed as obese using BMI.

The study showed that patients with obese levels of BMI were four times more likely to die of heart disease than those of normal weight, while a waistline that fell into the obese category increased the risk three-fold.

Earlier studies had suggested that obesity roughly doubled the chances of dying from heart disease.

Extrapolated to the general population, it would mean one third of all fatal cardiovascular disease cases and one in seven of non-fatal cases can be ascribed to being overweight and obesity, the researchers said.

The study, published in the European Journal of Cardiovascular Prevention and Rehabilitation, a journal of the European Society of Cardiology, involved 20,000 Dutch men and women aged between 20 and 65 who were measured by health professionals and followed-up for ten years.

Almost one in four adults in England are classified as obese and by 2050 only one in ten people is predicted to be a healthy weight. It means the impact of obesity will be even greater in the future, the researchers said.

A body mass index of 30 or more classifies as obese, with a healthy BMI of between 18.5 and 24.9.

Principal investigator Ineke van Dis from the Netherlands Heart Foundation said: " What this study shows is the substantial effect which overweight and obesity have on cardiovascular disease, whether fatal or non-fatal. In the near future the impact of obesity on the burden of heart disease will be even greater.

"These findings underline the need for policies and activities to prevent overweight in the general population. And I think that general practitioners and cardiologists can do even more to tackle these problems, especially in obese patients under 65 years, as highlighted in this study."

Fotini Rozakeas, cardiac nurse at the British Heart Foundation (BHF), said: "This study shows that in people between the ages of 20 and 65 years old, body mass index (BMI) and waist circumference (WC) measurements are powerful predictors of the risk of having cardiovascular disease.

“With the incidence of being overweight or obese in the UK predicted to almost double by 2015, measuring BMI and WC in general health checks is an inexpensive, simple measure to assess health risk and can reduce the burden of developing and living with debilitating conditions.

“Whilst people can follow healthy diets and take regular exercise, policy-makers must support them by shaping the environment to make healthy choices easier. One opportunity is to make food labels clear and consistent to help shoppers consider healthier options”.